Related papers: SDSSJ212531.92-010745.9 - the first definite PG115…

We conducted time-resolved optical spectroscopy and/or photometry of ten cataclysmic binaries that were discovered in hard X-ray surveys, with the goal of measuring their orbital periods and searching for evidence that they are magnetic.…

We have discovered that the brown dwarf WISEJ014656.66+423410.0 is a close binary (0.0875$\pm$0.0021 arcsec, 0.93$^{+0.12}_{-0.16}$ AU) from Keck laser guide star adaptive optics imaging. Our photometry for this system reveals that both…

ROTSE1 J164341.65+251748.1 was photometrically observed in the V band during three epochs with the 0.84-m telescope of the San Pedro M\'artir Observatory in Mexico. Based on additional BVR photometry, we find that the primary star has a…

We report the discovery during the Parkes Multibeam Pulsar Survey of PSR J1756-2251, a 28.5 ms pulsar in a relativistic binary system. Subsequent timing observations showed the pulsar to have an orbital period of 7.67 hrs and an…

We have identified 2XMM J125556.57+565846.4, at a distance of 600 pc, as a binary system consisting of a normal star and a probable dormant neutron star. Optical spectra exhibit a slightly evolved F-type single star, displaying periodic…

We performed time-series photometry of the PG1159-type star HE 1429-1209, which was recently discovered in the ESO SPY survey. We show that the star is a low-amplitude (about 0.05 mag) non-radial g-mode pulsator with a period of 919s. HE…

The binary system PSR B1259-63/LS 2883 consists of a 47.8 ms radio pulsar that orbits the companion Be star with a period of 3.4 years in a highly eccentric orbit. The system is well sampled in radio, X-rays, and TeV gamma-rays, and shows…

Low-mass stars in eclipsing binary systems show radii larger and effective temperatures lower than theoretical stellar models predict for isolated stars with the same masses. Eclipsing binaries with low-mass components are hard to find due…

We report the detection of orbital decay in the 12.75-min, detached binary white dwarf (WD) SDSS J065133.338+284423.37 (hereafter J0651). Our photometric observations over a 13-month baseline constrain the orbital period to 765.206543(55) s…

We present simultaneous spectral and photometric observations of SDSS J123813.73-033933.0. From Ha radial velocity measurements we determined the orbital period of the system to be 0.05592+/-0.00002 days (80.53 min). The spectrum shows…

The observational mass-radius relation of main sequence stars with masses between ~0.3 and 1.0 Msun reveals deviations between the stellar radii predicted by models and the observed radii of stars in detached binaries. We generate an…

The pulsar PSR B1259-63 is in a highly eccentric 3.4-yr orbit with the Be star SS 2883. Timing observations of this pulsar, made over a 7-yr period using the Parkes 64-m radio telescope, cover two periastron passages, in 1990 August and…

We present the analysis of time-resolved spectroscopy of the pulsating sdB star PG1605+072. From our main observing run of 16 nights we have detected velocity variations at 5 frequencies that correspond to those found in photometry. Based…

The double pulsar system PSR J0737-3039A/B is a double neutron star binary, with a 2.4-hour orbital period, which has allowed measurement of relativistic orbital perturbations to high precision. The low mass of the second-formed neutron…

An asteroseismological study of PG 1159-035, the prototype of the GW Vir variable stars, has been performed on the basis of detailed and full PG1159 evolutionary models presented by Miller Bertolami & Althaus (2006). We carried out…

PG 1159-035, a pre-white dwarf with T=140000 K, is the prototype of the PG1159 spectroscopic class and the DOV pulsating class. Changes in the star cause variations in its oscillation periods. The measurement of temporal change in the…

Our discovery of 1SWASP J093010.78+533859.5 as a probable doubly eclipsing quadruple system containing a contact binary with P~0.23 d and a detached binary with P~1.31 d was announced in 2013. Subsequently Koo et al. confirmed the detached…

We present the first multi-band optical light curves of PSR J1622-0315, among the most compact known redback binary millisecond pulsars, with an orbital period Porb=3.9 h. We find a flux modulation with two maxima per orbital cycle and a…

The millisecond pulsar PSR B1259-63 and the Be star SS2883 are situated in a highly eccentric binary system, with orbital period ~3.4 years. We report on hard X-ray observations obtained with the INTEGRAL satellite close to the 2004…

PSR J1910-5959A is a binary pulsar with a helium white dwarf companion located about 6 arcmin from the center of the globular cluster NGC6752. Based on 12 years of observations at the Parkes radio telescope, the relativistic Shapiro delay…